Imiprovement in force-pumps



Patented March 21, 1876.

Gqw. GJLMORE.

FORCE-PUMP.

NAPEERE. FMOTO-LITKOGRFHER. WASHINGTON. D. C.

UNITED STATES GEORGE W. GILMORE, OF'WEBSTER, PENNSYLVANIA.

IMPROVEMENT IN FORCE-PUMPS.

Specification forming part of Letters Patent No. 174,904, dated March 21, 1876; application filed August 6, 1875.

Toall whom it may concern Be it known that I, GEORGE W. GILMORE, I

admitting air to the barrel above the pist0n,

where it is compressed by the upward stroke, and forced into the hollow piston, for the purpose of giving greater force to the expulsion o f the liquid from the pump by the downward stroke ot' the-piston.

The drawing exhibits a vertical section of' a force-pump provided with the improved piston elsewhere described, and the valve for admitting'air to the pump-barrel.

A is the pump-barrel.l A is the discharge pipe. B is the hollow piston, andB is therod. C C are valves connected together, which open and close alternately the openings a a and b b in the top and bottom of the piston, respectively, the chamber F in the piston being for the reception of the compressed air admitted by the upward stroke. G is the cap or top of the pump, provided with a stutli ngbox, H, through which the rod plays. I I are openings 'in the ca-p for the admission of air. K is a stirrup attached to the under side of the cap that supportsl the spiral spring L, which holds the valve M in its seat to close the openings I I.

The operationof the invention is as follows The piston B being forced down, the pressure of the air on the valve M opens it, and the the piston are opened and the upper valves. closed, confiningthe air, which thereupon v rushes out of the valves b b, and presses on the water or other liquid, which has been raised in the pump-barrel, and this pressure of they compressed air, added to that of the piston on the liquid, forces it through the discharge-pipe A with much greater force and velocity than would be obtained by the pressure of the piston alone.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

lhe openings I I and valve M, in combination with the piston 4 B, constructed substantially as described and set forth.

GEORGE W. GILMORE.

Witnesses WM. M. OUTHBERT, J oEN F. MILLER.

PATENT OFFICE. 

